package zjh_20230308;

public class Main {
    public static void main(String[] args) {
        arrayList arrayList = new arrayList();
        System.out.println( arrayList.add("aaa"));
        System.out.println( arrayList.add("bbb"));
        System.out.println( arrayList.add("ccc"));
        System.out.println( arrayList.add("ddd"));

        arrayList.add(0,"111");

//        arrayList.clear();

//        System.out.println(arrayList.isEmpty());
//        System.out.println(arrayList.size());
//        arrayList arrayList1t = new arrayList();

//        System.out.println(arrayList.equals(arrayList1t));
//        Object x = arrayList.remove(0);
//        System.out.println(x);
        Object[] objects = arrayList.toArray();
        System.out.println(objects);
        int num = arrayList.indexOf("aaa");
        System.out.println(num);
        boolean x = arrayList.contain("ccc");
        System.out.println(x);
        boolean x1 = arrayList.contain("222");
        System.out.println(x1);
    }
}